To gather life-saving surgery money for his younger sister, pet veterinarian Su Ming accepts a zookeeper position at Chang'an Zoo with a daily wage of eight thousand. On his first day of employment, the director hands him a set of weird uniforms and strange rules, strictly forbidding him from stepping out of the park and prohibiting him from treating any animals. But late at night, the exotic beast Zishu goes berserk, iron chains rattling as they are bitten, and Su Ming cannot bear it, violating rules to administer treatment, pulling a black iron block out from its body during tooth replacement. Coincidentally, an S-class exotic beast is rampaging and causing chaos outside the city. Su Ming continues to venture into treating animals within the park, gradually uncovering the weird secrets hidden within the animals. Ultimately, Su Ming resolves to cure all trapped animals with medical skill, letting them return to normal.